In an apparent effort to defuse tensions over a major spy controversy, East Germany has vowed to remove all remaining mine fields along the East-West border and to expand human contacts between the German states, Bonn officials said today.

Communist East Germany's head of state, Erich Honecker, conveyed the pledges to the conservative West German politician Franz Josef Strauss at yesterday's opening of the Leipzig trade fair, according to the Bonn government spokesman, Friedrich Ost.

Honecker promised that all mines would be eliminated along the border by the end of the month and that security rules inhibiting more than 3 million East Germans from reaching friends and relatives in the West would be relaxed, Ost said.

West German Foreign Ministry officials said Honecker's comments evidently were intended to overcome suspicion and distrust affecting links following the defection of several secret agents and a leading counterspy to the East.

Security authorities revealed today that Hans Joachim Tiedge, a top-ranking officer in West Germany's counterintelligence service who was in charge of tracking East German agents, explained in a letter to the Bonn government that he felt compelled to flee to the East last month because he was mired in a "hopeless situation" -- an evident allusion to problems with debt and alcohol.

The letter, which officials confirmed was in Tiedge's handwriting, marked the first contact between the defector and West German authorities since he disappeared Aug. 19.

Ost said East Berlin authorities have been seeking to arrange a meeting with Martin Winkler, an East German diplomat in Buenos Aires who defected to the West Aug. 25. He said Winkler refused.

While the Bonn government has denied any direct link between the two betrayals, security sources have contended that Winkler was a West German agent who bolted his cover because he feared he would be exposed after Tiedge arrived in East Berlin.

In the talks with Strauss and other West German representatives, Honecker reportedly said that current difficulties caused by the spy controversy must be "brought under control" and exhorted both governments "to work harder than before" to improve trade and human relations. His promises amounted to a reiteration of previous vows that have been left unfulfilled, West German authorities said.

The apparent concession offered by Honecker to ease human contacts across the border was received in Bonn with restrained approval. An official said Bonn would "wait and see" whether family reunification rights will be extended to "second-degree relatives" rather than remain restricted to husbands, wives, parents and children.

Officials said that East Germany has been removing mine fields along the border for several years and that only 25 miles of the 800-mile frontier are still seeded with explosive devices. The border has been reinforced by more sophisticated alarm systems and higher fences that could make attempts to escape East Germany more arduous than in the past.